The invention relates to a cutting tool that facilitates direction-changing during cutting therewith to form complicated cut pieces from sheet material. This is especially useful when the cutter is automatically moved during cutting (no close operator control being provided) to prevent binding of the tool in the material being cut (especially sheet metal) when turns at sharp angles are being made. While there are numerous types of cutters, both hand and automatic, in the prior art, such as shown in U.S. Pat. Nos. 2,750,667 and 3,710,445, it is believed that none of such cutters provided for the easy direction-changing cutting movement according to the cutter of the present invention.
The cutting tool according to the present invention comprises an upper blade adapted to be disposed above the surface of a horizontally disposed metal sheet to be cut, a lower blade adapted to be disposed below the surface of a horizontally disposed metal sheet to be cut, and having a leading and trailing edge, and means for moving at least one of the blades with respect to the other blade to effect cutting of the metal sheet. An arm mounts the lower blade in position below the sheet, and a ball bearing is mounted on the arm, and has a portion thereof extending upwardly from the arm, said ball bearing being mounted adjacent the trailing edge of the lower blade and for engaging the bottom surface of the metal sheet to allow easier pivoting of the cutting tool during cutting to change the direction of cutting. Preferably the ball bearing is spring-biased into engagement with the bottom of the metal sheet, and the lower blade is relatively stationary, the upper blade being movable with respect thereto. Also, the arm is preferably a lever pivotal about a generally horizontal axis during horizontal cutting at a pivot point, the ball bearing being mounted adjacent the pivot point on one side thereof and the trailing edge of the lower blade being mounted adjacent the pivot on the other side thereof opposite the side said ball bearing is disposed.
It is the primary object of the present invention to provide an improved cutting tool for cutting sharp angles and curvatures in sheet metal. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.